Disazo and polyazo benzidine type dyestuffs



- Patented July '16, 1946 DISAZOJAND POLYAZO BENZIDINE TYPE DYESTUFFS Fritz Straub, Kaiseraugst, near Basel, and Jakob Brassel, Basel, Switzerland, .assignors to Society of Chemical Industry in Basle, Basel, Switzerland, a Swiss firm No Drawing. Application August 23, 1943, Serial Nc." 499,707. In Switzerland September 3,

-15 Claims.

The present invention is conce'rned with disazo and polyazo'dyestuifs, more particularly those of the direct dyeing (i. e. substantive) series. Still v more particularly it is. an object of thepresent invention to provide new dyestuffs capable. of forming complex metal compounds, especially such dyestuffs of the saidseries,[ the complex metal compounds of which are substantially ,insoluble in normal baths used for textile treatments, whereas the parent dyestuffs free from complex bound metal areper fectly. soluble and can be d e n-t w u w wT is stwng .demand for such dyestuffs, especially since the ;sim le and effective-dyeing method of 'U. S. Pat- -ent.2,148,659 (ct-also French Patent;80,9 ,893) has become known, .Especially dyestuffs dyeing red shades, such asare obtainable according tothe present invention, are highly. valued. Prior to t his invention, numerous dyestuffs derived (from benzidine-and dianisidine havebecome known.

Due to the lack of complex-forming groups in ortho-position to the azo-groups in the benzidine dyestuffs, these are not capable of forming complex metal, compounds unless coupling ,components are used .which are by themselves (i. e. without the aid-10f, a complex form-in'ggroup in the diazo component) capable of forming complex metal compounds, such as salicylic acid or ortho: ortho'-dihydroxy-azo-dyestufis capable of coupling, etc. Thereby the choicof coupling components is obviously very restricted; The methoxy groups in ortho-position to the azo groups in the dianisidine dyestuffs act, it is true, as complex forming groups, but the complex metal compounds obtained with these dyestuffs are rather unstable and often do not withstand even mild soaping.

Furthermore, it is well known in the art that many valuable acid wool dyestuffs are obtained with coupling components of the pyrazolone se-;

' ries.? As far as we are aware, nothing was known prior to the present invention which would indicate a beneficial effect to be expected in using pyrazolone coupling components in the manufacture of-substantive azo dyestuffs of thev said kind.

It has been found that valuable disazo and polyazo. dyestuffs may be obtained by coupling tetrazo compounds with azo components, if desired by using further couplingor connectingre-q I actions, if as a tetrazo compound tetrazotized 3- hydroxy-4:4-diaminodiphenyl, and, as at least one, azo component a pyrazolone are used and, if desired, causing agents yielding metal toreact with; the dyestuffs thus ,obtained.',

. r 2 a The'tetrazotization of the 3-hydroxybenzi dine may be conducted in known manner, for .in-

stance in a hydrochloric acid solution.

For the coupling with the tetrazotized 3-hydroxy-benzidine there may be usedtwo molecular proportions of the same or different coupling components of which, however, at least one must be a pyrazolone.

Further azo components to be united with the tetrazotized 3-hydroxybenzidine may belong, for instance to the benzene, or naphthalene se- .ri es,; ;po ssess a heterocyclic ystem, '-or contain a. carbon atom capable of coupling in an open chain-There mayfor. instance be mentioned phenols and particularlysalicylic' acids, resorcinol, naphthols, naphthol-monoand -dis ulfonic acids, aminonaphthols and the sulfonic acids thereof. Among the pyrazolones there come particularly into consideration such products which are substituted in knownmanner, for instance, by an aryl radical in l-position and/or bya .methyl or carboxyl group in 3-position. In. this case also the aryl nucleus, for example the benzene nucleus, may carry substituents such as for example a sulfamide, nitro or amin group, as

well as the salicylic acid grouping. I j

Particularly valuable dyestuffs are in many I 'cases'obtained if as at least one azo component such a component is used which-contains the be present in the pyrazolones, such as in the case salicylic acid grouping. This grouping may also of 1-(3'-carboxy-4'-hydroxyphenyl)-3- methyl-5-pyrazolone.

. In his manner a great number of very valuable disazo dyestuffs may be obtained according to the. present invention. For the production of trisazo and polyazo dyestuffs there are advan tageously used azo components which contain an amino group capable of further diazotization or a substituent convertible into such a, group. Further also such azo components. may be used which are capable of repeated coupling, 'or also such components which lend themselves to other connecting reactions leading to the synthesis of polyazo dyestuffs, such as urea formation, reductive connection of two nitro groups, etc. As examples there are mentioned 1-(3'-aminophenyl)- 3-methyl-5-pyrazolone, 2-amino-5-hydroxynaph thalene-7-sulfonic acid, resorcinol and 5:5'-dihydroxy-2i2'-dinaphthylamino 7:7 disulfonic acid. The dyestuffs thus obtained may then be converted in known manner into trisazo or polyago dyestufis. Furthermore, trisazo and polyazo dyestuffs are of course obtained by using coupling components containing azo groups in at leastone place, for example azo dyestuffs containing a carbon atom capable of coupling in a benzene ring I (such as mono-coupled resorc'inol dyestufis) or in a naphthalene ring-(such as aZodyestufisirOm any -diazo compounds and am'ino naphtholsulj fonic acids coupled in an acid medium), etc.

It is to be remarked that the two diazonimnj groups in tetrazotized 3-hydroxy -4 :A 'H-liiaminQ-H 3 diphenyl possess a rather differentcouplinggen-i.

ergy, in that the 4'-diazonium group couples first" andthe 4-diazonium groupecin lort'ho position :to'

the 3-hydroxyl group) afterwards. jml rei eforegitf stirred for 1 hour at 10-12 C. and for 20 hours at 15-20" C. The dyestufi' is precipitated by the addition of common salt. When dry, it is a dark =powderof the -formula coon is well possible, and in many ins'tancesipi-efier'ab le;

l to unite the said tetrazo compounds with two dif- 1 ferent coupling components; jllhus -:the component may be selected tocontaina grouping capable of forming complex metal compounds by I j cially cotton linen, rayongand staple fibersfrom regenerated cellulose; very ya'luablered; shades, Q n

7 among other shades, are also obtained.

Favorable results are obtained if g ii'flireiir im end n o it t particuiarlysulfonicfacid groups isiconst'ituted 'insu ch*a i nanner that alsoits complex-'metal I V v I Q whcle is stirred for 1" hour at -42 C: and a compounds produced in substance, for "instance gccmplex ccpper compounds, are soluble, the latc 5 termay be produced known-manner and used i for dyein'g. Dyeings'of particularly good fastne'ss to' wet treatments are obtained inmany in- V completed by heating the mixture i-"foi *2'fi3'05h011rs stances with such dyestuffs, obtainaible according to the presentjinvention;whose complex metal j 'compound are sparingly soluble to'insolume.

use i made oi such dyestuffs it -is "of advanta e after-coppering process, orm'or'esimplyaccord ing to the dyeing process-known for-example from 1. the U. S; Patent "No; 1148;6 59 *(see also. Frenc'h Patent No. 809,893) according towhichidyeing is conducted in' the; same bath as theafteir-treatmien-twith agents yielding meta-l, particularly agents yielding copper. Such agents yielding icoppermainly come into consideration which are stable towards alkal'ie's, such complex copper "tartrates, H 7 V I [The following examples 'illu'strateithe invenj Iti'o'n; thepartsbeingby weight:

Example 1 A aidd'edto the coupling mixture; The mixture is l w h'ich ii'issolves water to an orange-brown, in

dilute alkaliesto' an orange-red and in concentrated sulfuric acid to a ruby-red solution and dyes vegetable fibers red tints which are fast to washing and light on' 'beingdyed and coppered I 556' parts of;'fl hydroxybenriidme are tetrazoand in ithepresence bf hydio hlbflc ac'idf The clear, solution of the tetrazocompound is added 5 *at 1-01-15" "C: 'to a solution" alkalinewith sodium I carbonate of- 7173, parts-of the dyestuff prepared by vcoupling l moL-flo'f diazotized fZ-am'ino-I- phenol-4 su-l'famide'with l-mol'. "6f resorcinol in a medium alkaline with sodium carbonate. The

i l'one is 'addedto the-coupling mixture} i tn ringis/ "continued for l'hour a't "IE-1 8C. and coupling'is f to 40" c. The trisazo' 'dyestiiil crtnerdimun v and hydrochloric acid. When dry, it is agreen powdero'f bronze l-us'tre,-' whlch-diss'olves in water "anddilute So'c fium -carbOIIate sermon: tore bor- "d'eaux red,*in dilute caustic alkalies to a; brown redand i in concentrated hydrochloric acid a dichrdic 'red -blue -soluti on-wliich" dyes vegetable fibers iiolet *brownshades *Wlfi'flh are' fast to --washmg on being dyed'fl and-coppered according tothe onebath'process; Similar dyestuffs having t-he same-' fastness i tifzed "with sodium 'nitrite-in theusual manner ncomes I properties canbe obtained by replacingthe 2- amino-1-phenol-4-sulfamide v.used in this example by other ortho-aminophenols,for-example by the equivalent quantity of 4-nitro-2-a'mino-1- phenol. *5

Example 3 5 parts of 3-hydroxybenzidine are tetrazotized with sodium nitrite in usual manner and in the presence of hydrochloric acid. The solution of the tetrazo. compound isadded at 5 C. to a solution of- 3.46 parts ofsalicylicacid and-6,.p'arts of sodium hydroxide in 40 parts of'water. The whole is stirred for hour. at .4-.6 Cs; a solution 'of 4.73 parts of 1-'(3'-aminophenyl)-.3- methyl-5-pyrazolone and 2 parts of sodium hydroxide in 50 parts of water is added and stirring is continued for-1 hour. at:10-12. C..: and -25 hours at:I5-20 C. "After-neutralizing with hydrochlorlc acid the disazo-dyestufi'is filtered-janddis- Q0 solved by the addition of 1.2 parts of sodium hydroxide in 400 parts of water. parts byvolume of N-sodium nitrite solution are added to the dyestuffsolutioncand themixture is cooled to 5 C. 60 parts by volume of.E21 I.-hydrochloric acid are ured to the.solution=-while stirringwell. The te'mperatureis maintained for 15-20 hours at 10-15" C; and the diazodisazo-dyestufiis filtered; This is introduced, in theform-of a moist'paste, into a solution of 5.85 parts of1-- (4-hydroxy-3'-carboxyphenyl) .-'3-methyl-5-'pyrazolone and '6 parts of sodium hydroxide .in 90 parts of water. Stirring is continued for. 1 hour at 10-12 C; and coupling is completedat 18'20;C.

Example 4 100 parts of cotton are introduced at 50 G. into a dyebath containing in 2500 parts of water 2 parts of sodium carbonate and 1.5 parts of the dyestuff prepared according to Example 1, first paragraph, and the temperature is slowly raised to 90-95 C. 30 parts of Glaubers salt are added after /4, hour and-dyeing is continued at this temperature fo a further /1 hour. The bath is then cooled to about 70 C., the necessary quantity of a solution of complex copper tartrate made feebly alkaline with sodium carbonate is added and the material is coppered at 80-90 C. for /2 hour. It is then thoroughly rinsed and soalped for fast red tints.

What we claim is:

- -1.- Azo dyestuffs ofthe general formula j 4 ,wherein R stands fontlie radical of a" coupling component selected-fromthose belonging to the benzene and naphthalene series and Rastandsfor the radical of a pyrazolone coupling component.

. AZO d es f i e ne a! e al 1 wherein R stands for the radical of a coupling component selected from those belonging to. the

ponents containing a grouping capable of form;

ing complex metalcompounds. by itself. 3. Azo dyestuffs, of the general formula wherein stands for the radical of a coupling component selected from those belonging to the benzene and naphthalene series, and Pa stands for the radical of a pyrazolone coupling component, at least one of the said coupling components containin a salicyclic acid grouping. O dyestuffs of the rgeneralaformul wherein R' stands for the radical of acOupIing component, selected from those belonging to the benzene and naphthalene series, containing a grouping capable of forming complex metal compounds by itself, and Pa stands for a pyrazolone coupling component.

5. A20 dyestuffs of the general formula wherein R stands for the radical of a coupling component, selected from those belonging to the benzene and naphthalene series, containing a grouping capable of forming complex metal compounds by itself, and P2 stands for a pyrazolone coupling component also containing a grouping capable of forming complex metal compounds by itself.

6. Am dyestuffs of the general formula wherein R stands for the radical of a coupling 1 component, selected from those belonging to the benzene and naphthalene series, containing a grouping capable of forming complex metal compounds by itself, Pz stands for the radical of a =pyrazolone coupling component, and wherein at least one of the components R and Pa contains I coon v on 

